Cleaning apparatus

ABSTRACT

A cleaning apparatus comprises a reservoir for containing a body of foamable material in unfoamed state. Converting means is connected with the reservoir for receiving from the latter unfoamed material and for converting this into foamed state. Moving means mounts the reservoir and converting means for movement over a surface to which the material is to be applied in unfoamed state.

United States Patent Leifheit et al. 5] Oct. 10, 1972 54] CLEANING APPARATUS [56] References Cited [72] inventors: Giinter Leifheit; Johannes UNITED STATES PATENTS Liebsch b th f N Lah assau/ 3,212,117 10/1965 Ernstberger et a1 ..15/50 R 3,224,023 12/1965 Brodie ..15/50 R Asslgneel Lqfhelt International Gunter Lelf- 3,041,644 7/1962 Wallace ..15/50C h n K Nassau-Lahn, Germany 3,246,360 4/1966 Yonkers ..401/218 x 221 Filed: Dec. 2, 1969 Primary ExaminerEdward L. Roberts [21 APPI- NOJ 881,440 Att0rney-Michael S. Striker 30] Foreign Application Priority Data [57] ABSTRACT Dec. 2, 1968 Germany ..P 18 1 5 A cleaning apparatus comprises a reservoir for containing a body of foamable material in unfoamed state. 52 U.s.'cl ..15/50 0, 401/197, 4011224 Converting means is connected with the reservoir for 51 lm. Cl. ..A47l 11/03 receiving from the latter material and [58] Field of Search ..15/49, 49 R, 49 c, 50, 50 c, Converting this into foamed means mounts the reservoir and converting means for movement over a surface to which the material is to be applied in unfoamed state.

' 12 Claims, 16 Drawing Figures I I I I I I I I I I j I I I PKTENTEDHM 10 I972 SHEET 2 0F 5 FIGS FIG.6

N VEN TOR Guurez 46mm? PKTENTED 10 I912 3 696. 458

saw u 0F 5- I MWWX g IN VENTOR wr'n Jew/5nm 5, ym I CLEANING APPARATUS BACKGROUND OF THE INVENTION The present invention relates generally to cleaning apparatus, and more particularly to an apparatus for producing and applying foamed cleansing materials.

It is already known to provide apparatus which moves over the surface of an article to be cleaned and applies to this article a foam-type cleaner, that is a cleaning substance which is applied in foamed condition. The problem with these known devices is the fact that the conversion of cleaning substance from unfoamed state into foamed condition provides significant difficulties. In order to obtain maximum cleaning effect without undesired side effects-that is without excessive wetting of the article to be cleanedit is necessary that the cleanser which of course is usually a liquid, be completely converted to foamed state so that the foam thus obtained is of almost dry consistency.

This, however, has heretofore been impossible to achieve with the apparatus known from the prior art and industry and therefore long sought for an improvement which until now has not been forthcoming.

SUMMARY OF THE INVENTION It is, accordingly, an object of the present invention 7 to provide improved cleaning apparatus of the type under discussion.

More particularly it is an object of the present invention to provide such a cleaning apparatus which is not possessed of the aforementioned disadvantages.

Still more specifically it is an object of the present invention to provide such a cleaning apparatus which makes it possible to convert a liquid cleanser completely to foamed state, with the foam thus obtained being of almost completely dry consistency.

An additional object of the invention is to provide such an apparatus which is simple and relatively inexpensive to construct, but which is very reliable in its operation.

In pursuance of the above objects, and others which will become apparent hereafter, one feature of the invention resides in a cleaning apparatus which comprises, briefly stated, reservoir means for a body of foamable material in unfoamed state. Converting means is connected with the reservoir means for receiving from the latter unfoamed material, and for converting such material to foamed state. Moving means mounts the reservoir and converting means for movement over a surface to which the material is to be applied in foamed state.

Thus, by alternately compressing and subsequently relaxing the foam-producing element of the converting means, namely an absorbent resiliently compressible element, an intensive admixture of air with the liquid cleanser takes place, converting the same into a foam of near dry consistency.

According to one embodiment of the invention a hollow cylinder which is apertured over part or all of its circumference is provided, with the absorbent resilient compressible element being located on the interior and secured against movement with reference to the cylinder, and with one or several press rollers and being located in the interior of the cylinder pressing against the absorbent element with a movement between the pressure rollers and the hollow cylinder being, of

course, a requisite in this case. With such a construction all portions of the absorbent element are successively compressed and relaxed and the foam can escape to the exterior through the apertures in the hollow cylinder.

A further embodiment of the invention provides for the absorbent element to be an endless preferably annular sheet material member. Such a sheet material member is supplied to the pressure rollers without any interruption and can advantageously be mounted on the interior of the hollow cylinder immovable with reference to the latter.

According to a preferred embodiment the hollow cylinder may be mounted stationarily at the housing of the apparatus and one or more pressure rollers may be rotated about its inner circumference in opposite directions, depending upon the direction of movement of the apparatus. In this case other components of the apparatus, preferably wheels on which the apparatus is advanced, are connected in motion transmitting relationship with the pressure roller or pressure rollers to cause movement of the same. In this embodiment the pressure roller orbits about the inner circumference of the hollow cylinder.

A further embodiment of the invention envisions the arrangement of the hollow cylinder turnably mounted on the housing of the apparatus, with the absorbent element again being fast with its inner circumferential surface. One or more pressure rollers are then mounted at the interior of the hollow cylinder in axial parallelism therewith for rotation about their longitudinal axis, but without freedom of orbital movement. This is a very simple construction which is accordingly inexpensive. The pressure roller or pressure rollers may itself be hollow and mounted on a portion of a hollow shaft, with both the pressure roller and the hollow shaft being provided with apertures and with the hollow shaft communicating with the reservoir so that liquid from the reservoir passes through the hollow shaft and out through the apertures of the pressure roller into the material of the absorbent element.

With the just mentioned construction it is not necessary to provide a separate supply pipe or conduit for the liquid to be foamed, and this of course again simplilies the construction of the device and reduces its expense. It is advantageous but not absolutely necessary that the hollow cylinder rolls with its outer circumferential surface directly on the material which is to be treated with the foam produced. In this case the hollow cylinder itself acts as the foam applicator and obviates the necessity of a separate applicator member.

It is emphasized that if desired or necessary a separate supply conduit may be provided a portion of which is then arranged in the space between the absorbent element and the pressure roller, or one of them if there are several, and which is apertured so as to discharge onto the absorbent element the liquid to be foamed. Such a construction has the advantage that liquid entering from the reservoir can be evenly distributed over the entire width-or rather axial lengthof the pressure roller.

It is also possible to mount the absorbent element between cylindrical pressure rollers, with either the latter, the former, or both being movable relative to the respectively other component, motion being transmitted preferably but not necessarily through the wheels on which the apparatus passes over the surface of the article to be treated. Such a construction is still simpler than others mentioned before and therefore less expensive without, however, being any less effective. If desired, and in order to increase the development of foam in dependence upon the quantity of incoming foamed cleaning liquid, one or all pressure rollers may be provided with a coating or covering of elastically compressible absorbent material which may but need not be the same as the material of the absorbent element. In addition, means may be provided for effecting turning movement of the pressure roller and/or the hollow cylindrical member and/or the absorbent element-depending upon which of them movesalways in one and the same direction regardless of the direction in which the apparatus itself is moved. This provides for a further increase in the density of foam used, so that the latter is still drier.

The absorbent element may also be of substantially cylindrical configuration and located within a cage consisting of a plurality of circumferentially spaced rod-like pressure rollers, in which case a plurality of circumferentially spaced portions of the absorbent element are subjected to compression simultaneously, with the portions inbetween being allowed to expand at the same time. The re-absorption of the foam in the expansion areas located intermediate the respective rodshaped pressure rollers can be avoided by having the foam pass over the exterior of the pressure rollers so that it becomes deflected out of contact with the surface of the absorbent element. It is advantageous to make the pressure rollers turnable about their longitudinal axes in order to require drive forces which are as low as possible.

The absorbent element may also be constructed in the form of a plurality of sections having a certain diameter, with drive discs located between and in contact with successive ones of the sections and having a diameter larger than the diameter of the sections. These discs may also serve for effecting the necessary compression of the sections of the absorbent element, in this case from opposite axial sides of the latter. For this purpose the discs may be axially inclined towards one another, for instance by mounting them and the sections of the absorbent element on a curved shaft.

Applicator rollers may be provided which are advantageously located immediately downstream of the areas where the absorbent element is subjected to compression, so that the applicator rollers carry away the foam produced in such areas for applying it to the article to be treated with the foam, before the foam can be reabsorbed in the areas where the absorbent element undergoes expansion. This has the additional advantage that in the areas which undergo expansion or relaxation, the pores of the absorbent element remain free to absorb air, rather than becoming clogged with the foam, so that this facilitates the production of better foam.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a diagrammatic cross-section through one embodiment according to the present invention;

FIG. 2 is a partially broken away top view of a fragment of the embodiment illustrated in FIG. 1;

FIG. 3 is a fragmentary top view of a detail according to a further embodiment;

FIG. 3a is an end view of FIG. 3;

FIG. 4 is a view similar to FIG. 3 but illustrating yet an additional embodiment;

FIG. 4a is an end view of FIG. 4;

FIG. 5 is a fragmentary vertical section through an apparatus according to yet another embodiment of the invention;

FIG. 6 is a diagrammatic side view illustrating a further embodiment of the invention;

FIG. 7 is a fragmentary vertical section illustrating a detail of another embodiment of the invention;

FIG. 8 is a view similar to FIG. 7 showing still a further embodiment of the invention;

FIG. 9 is a view similar to FIG. 8 but illustrating another embodiment;

FIG. 10 is a view similar to FIG. 9 showing yet a further embodiment of the invention;

FIG. 11 is a section on the line XI-XI of FIG. 10;

FIG. 12 is a fragmentary top view, partly broken away, showing another embodiment of the invention;

FIG. 13 is atop view of the embodiment of FIG. I2, but turned through and partly sectioned but not broken away; and

FIG. 14 is a section taken on line XIV-XIV of FIG. 12.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now the drawing in detail, and firstly the embodiment illustrated in FIGS. 1 and 2, it will be seen that the apparatus as a whole is identified with reference numeral 10. It comprises a housing 11 which may consist of various different materials, for instance synthetic plastic or metal, and which is provided with a reservoir 12 containing a body 13 of cleaning liquid in unfoamed state, but which is convertable into foamed state. An opening 14 is provided through which the cleaning liquid 13 is introduced into the reservoir 12, and a conduit 15 connects the interior of the reservoir 12 with a stationarily mounted hollow cylinder 16 which is arranged at the front of the housing 11.

In the illustrated embodiment the upwardly facing wall portions of the cylinder 16 are provided with apertures 17. Located in the interior and secured to the inner circumferencial wall of the cylinder l6for instance by adhesive meansis a circularly configurated absorbent element 18 of elastically compressible material. Cleaning liquid 13 passing through the conduit 15 into the interior of the cylinder 16 is absorbed by the material of the element 18. It will be appreciated that different materials are suitable for the element 18, but it is preferred that the material be a synthetic plastic open-celled foam material.

A pair of pressure rollers 19 and 20 are located in the interior of the hollow cylinder 16 and mounted with their opposite ends at two carriers 21 in such a manner that they are juxtaposed. The carriers 21 in turn are connected fast with a shaft 22 on which there are mounted the wheels 23 by means of which the apparatus moves over the surface of an article 27 to which foam is to be applied, in conjunction with the wheels 30 which are provided in the region of the reservoir 12. When the apparatus is moved in left or right hand direction as seen in FIG. 1, the wheels including the wheels 23 turn and thus drive via the shaft 22 and the carriers 21 the pressure rollers 19 and 20. The distance between these and the inner surface of the hollow cylinder 16 is smaller than the thickness of the element 18 so that, when the pressure rollers turn, they press against the element 18 and subject incremental portions thereof to compression which, as the rollers 19, 20 advance, are thereupon again allowed to relax. This alternate compression and relaxation of incremental portions of the element 18 causes excellent admixture of the air from the pores of the element 18 with the liquid 13 which has been absorbed into these pores, thus producing an intensive development of foam of nearly dry consistency.

The foam is produced at the interior of the hollow cylinder 16, and passes through the apertures 17 to the exterior where it is guided through a channel 24 to the applicator roller 25 which is arranged adjacent the hollow cylinder 16 and which is covered at the upper side by a portion 26 of the housing. The purpose of the applicator roller 25 is to provide for uniform application of the foam to the surface of the article-here assumed to be a rug or carpet-27 and for working the foam into the material of this article 27. The applicator and working-in effect may be further enhanced by providing the roller 25 with tufts of bristles, although as shown in FIGS. 3 and 4, it is also possible to construct the applicator roller 25 of axially adjacent discs 28 or annulae of teeth 29.

Normally the apparatus will have a handle by which it may be gripped, for instance a handle analogous to a broom handle, but this has not been shown because it is not essential for purposes of the present invention.

A further embodiment is illustrated insofar as necessary in FIG. 5. Here, a hollow cylinder 31 again carries at its inner surface an absorbent element 18. The cylinder 31 is turnably mounted in a box-shaped housing 32. It is provided with apertures 33 and has located in its interior a stationarily mounted pressure roller 34, which is rotatable about its longitudinal axis but does not orbit about the inner circumference of the cylinder 31.

In this embodiment the pressure roller 34 is mounted on a portion of a hollow shaft 35 and the latter, together with the pressure roller 34, is provided with aperturesthose of the pressure roller 34 being identified with reference numeral 37-through which the liquid 13 can pass to the exterior of the pressure roller to soak into or be absorbed by the absorbent element 18. The shaft 35, or of course its interior, communicates with the reservoir 36 via non-illustrated conduits.

The hollow cylinder 31 is rolled over the article 27 to be treated, whereby the element 18 is incrementally alternately compressed and relaxed and the foam is produced. The foam passes through the apertures 33 to the exterior of the hollow cylinder 31. The latter in this embodiment serves as its own applicator so that the applicator 35 of FIGS. 1 and 2 is not required.

An additional or, if desired, alternate possibility for supplying the liquid 13 to the interior of the pressure roller is still illustrated in FIG. 5. Specifically, we have illustrated a pipe 38 located above the pressure roller 34 and being provided at its underside with apertures 39 from which the cleaning liquid drips onto the pressure roller 34 for transmittal by the same to the absorbent element 18 which then absorbs the liquid.

A further embodiment of the invention is diagrammatically illustrated in FIG. 6. The pressure rollers are here configurated as rollers 40 and 41 which are driven in rotation by the wheels 42 (only one shown). Naturally, it is possible to have only one of the rollers driven by the wheels 42, for instance the roller 40, whereas the roller 41 in this case would be a freely rotating counterpressure roller.

The here annularly configurated absorbent element 18 passes between the rollers 40 and 41 in opposite rotational directions and dips with its lowermost increment into the liquid 13 which is not illustrated in FIG. 6 but for which a reservoir must of course then be appropriately positioned.

In the embodiment of FIG. 7 the liquid reservoir has also not been illustrated. However, this is not essential as long as it is kept in mind that the liquid passes from the reservoir in suitable manner to a roller element 44 where it is foamed in conjunction with two additional cylindrical or roller elements 45. The elements 44 and 45 have axes 46 and 47 which are turnably mounted in a housing. They consistthat is the elements 44 and 45of an absorbent material, for instance a synthetic plastic open-celled foam material. They may, however, be provided with a cover of such material instead of consisting in their entirety of it. The spacing between the axes 46 and 47 is selected that at the contact areas between the rollers 44 and 45 there is always an increment compression of the synthetic plastic foam material. Thus, this results in foaming of the liquid 13 at the contact and pressure areas 48 and 49. The foam is identified with reference numeral 50 and it will be appreciated that, in dependence upon the direction of movement of the apparatus, it is removed by one or the other of the applicator brushes 51 and 52 which work it into the surface of the article to be treated.

In the embodiment of FIG. 7 the direction of rotation of the rollers 44 and 45 is identified by the associated arrows. This direction of rotation corresponds to a movement of the device towards the right in the Figure in which case the foam produced is directly removed by the applicator brush 51, whereas the foam produced at the area 49 initially collects until it comes into.contact with the roller 45 which cooperates with the brush 51. The foam from the area 48 adheres to the roller 45 and is also supplied to the brush 51 by rotation of the roller When the direction of advancement of the apparatus is changed, that is when the apparatus moves towards the left in FIG. 7, then the rollers 44 and 45 rotate in direction opposite their associated arrows, and the foam is then removed by the applicator brush 52 and worked into the material to be treated.

The wheels 53 are rigid with the shaft 46 of the roller 44 and serve to drive the latter and the roller 45. The roller 45 is rotated by virtue of the fact that it is in contact with the roller 44 which is rotated when the wheels 53 turn. However, it will be appreciated that separate drive means for the roller 45 may be provided, instead of the wheels 53.

In the embodiment of FIG. 8 the rollers 54 are alternately rotatable in dependence upon the direction of movement of the apparatus, by the wheels 55. The roller 56 is taken along in rotation by the rollers 54. In this embodiment the wheels 55 are automatically shiftable in direction opposite the direction of advancement of the device, by being mounted in slot-like substantially horizontal bearings with at least one of the wheels 55 being fast with an annular gear 57 which can be alternately brought into mesh with a transmission wheel 58 of the roller 54 by engagement of the outer circumference of the gear 57 with this transmission wheel, or with the transmission wheel 59 of the other roller by engagement with this transmission wheel 59 of the inner circumference of the gear 57. Instead of providing mesh contact, which requires the provision of cooperating gear teeth, it is also possible to provide frictional contact.

In this embodiment the rollers 54 and 56 will always rotate in one and the same direction, regardless in which direction the apparatus itself moves. Therefore, the area where the foam produced is removed, will always be unchanged so that only a single applicator brush 60 is necessary.

It is a particular advantage of this embodiment that the liquid 13 is converted to foam in two successive stages, being supplied to the roller 54 which is located at the left-hand side in FIG. 8. The roller 56 is provided with a cover or consists at least substantially itself of foam material in this embodiment. Because of this, there is an initial foaming of the liquid 13 which takes place at the pressure contact area 61 between the rollers 54 and 56. This partially foamed material is then supplied by the roller 56 to the pressure contact area 61 between the roller 56 and the roller 54 at which time the partially converted foam is again subjected to a foaming action, so that it is especially dense and almost completely dry before it is removed by the applicator brush 60. g

In addition to the advantages just mentioned, this embodiment has the further feature that no loss in the development of foam occurs when the apparatus shifts direction of movement, that is from the left to the right or from the right to the left in the drawing. Since it is customary to provide such reciprocatory movement for the apparatus, this embodiment assures that there is always an identical quantity of foam being supplied to the applicator brush 16 under all circumstances. Naturally, if it is desired the rollers 54 and 56 can also be driven in the direction opposite to that illustrated, if this is desirable for any reason, simply by making the necessary uncomplicated adjustment.

The element 62 illustrated in FIG. 9 corresponds to the element 18 of the preceding Figures in that it consists of absorbent elastically compressible material. However, this element 62 is located in a cage defined by a plurality of rod-like circumferentially arranged elongated pressure rollers 63, so that the element 62 is compressed in the region of the respective rollers or bodies 63. The liquid supplied to the element 62 is subjected to successive foaming upon rotation of element 62 before it is removed and carried away by the applicator brush 62, because the element 62 is successively compressed in the region of the respective bodies 63 and relaxed intermediate the same.

In this embodiment the element 62 which is of substantially cylindrical configuration is rotated by being drivingly connected with its supporting tubular axis 65 with the wheels 66. It is not necessary, but desirable and so illustrated in the embodiment of FIG. 9, that the bodies 63 are mounted for turning movement about their respective longitudinal axis so that they roll over the surface of the element 62. The configuration of the bodies 63 is such that the foam which is expressed by them from the element 62 moves over their outer sides and subsequently contacts the already relaxed increment of the element 62 downstream of the respective body 63. This prevents the once produced foam from being absorbed again into the pores of the element 62 as the same relaxes downstream of the respective body 63.

Functionally, the embodiment in FIGS. 10 and 11 corresponds largely to that of FIG. 7. Here, however, the absorbent element 67 is composed of a plurality of axially adjacent individual sections, with drive discs 68 being located intermediate successive ones of these sections, and with the sections and the discs 68 all being mounted on an axle 69. The drive discs 68 roll on the surface of an article to be treated when the apparatus is moved thereover, for instance on a carpet or rug, and thereby serve to turn the sections of the absorbent element 67 as well as the pressure bodies 70.

FIG. 11 shows that the drive disc 68 serves to locally compress the pressure bodies 70which in this case also consist of cellular foam materialso that free spaces remain between these and the sections of the element 67, in which spaces a portion of the foam may collect without being crushed again. The development of the foam and its transmission to the article to be treated takes place analogously to the embodiment in FIG. 7.

The embodiment illustrated in FIG. 12 comprises an absorbent element which is constituted of a plurality of sections 72 axially spaced and mounted on a straight shaft 71. Alternating with the sections 72 are pairs of drive discs 73 which are inclined to the axis and arranged substantially V-shaped. The discs 73 roll on the surface of an article to be treated and cause rotation of the sections 72 whereby the same are subjected to axial compression in the region of the smallest axial distance between the pairs of drive discs 73, so that the liquid 13 is converted to foam in this manner, with the foam being removed by an applicator brush 74. In the illustrated embodiment the applicator brush 74 is so constructed that its tufts of bristles engage into the spaces between two associated drive discs 73 and withdraw the foam which accumulates therein to thereupon work the foam into the material to be treated. The drive discs are provided with cutouts for passage of the foam and are guided in circumferential recesses of the applicator brush 74.

Finally, the embodiment illustrated in FIGS. 13 and 14 is analogous to that of FIG. 12 but differs from the same in that only a single pressure disc and drive disc is located between the successive sections 76 which together constitute the absorbent element. Some of the pressure discs 77 are configurated as drive discs which roll on the surface of the material to be treated and which have a significantly larger diameter than the sec tions 76. The actual compression of the sections 76 of the absorbent element in this embodiment takes place by making the shafts 78 on which the sections 76 and the discs 77 are mounted, of curved configuration with the concave side facing an applicator brush 79 which removes the foam produced and works it into the surface of the material to be treated.

While several embodiments have been illustrated herein it is emphasized that other embodiments are readily possible and will offer themselves to those skilled in the art. For instance, the absorbent elements may have different thicknesses, it may be provided with projections or recesses, or otherwise configurated. The number of absorbent elements, as well as of the various pressure rollers, may be varied in dependence upon the requirements, and the manner in which liquid is supplied and the supply of liquid is controlled may also be varied. Of course, the arrangement of the reservoir, its configuration and the configuration of the housing may be changed at will in dependence upon various requirements.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a cleaning apparatus, it is not intended to be limited to the details shown, since various modificationsand structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. A cleaning apparatus comprising reservoir means for a body of foamable material in unfoamed state; converting means connected with said reservoir means for receiving from the latter unfoamed material at a first location, and for converting such material to foamed state at a second location immediately proximal said first location, said converting means comprising at least one substantially cylindrical absorbent element having an outer surface, and compressing means engaging said outer surface at spaced portions thereof for subjecting increments of said absorbent element to compression in response to movement of said apparatus over a surface to which said material is to be applied in foamed state; moving means mounting said reservoir and converting means for movement over said surface to which i said material is to be applied; and aplplicator means for receiving the foamed material at at 1rd location closely adjacent said second location, and for applying the foamed material to said surface.

2. Apparatus as defined in claim 1, said absorbent element being mounted for turning movement with reference to said reservoir means; and wherein said compressing means is stationary but turnable with reference to said absorbentelement.

3. Apparatus as defined in claim 1, wherein said compressing mean comprises pressure rollers; and further comprising motion-transmitting means for effecting movement of at least one of said absorbent element and rollers with reference to the respectively other.

4. Apparatus as defined in claim 3; and further comprising a covering of absorbent elastically compressible material provided on the exterior of at least one of said pressure rollers.

5. Apparatus as defined in claim 1, wherein said compressing means comprises pressure members turnable about their respective longitudinal axes.

6. Apparatus as defined in claim 1, said absorbent element having a first diameter and comprising a plurality of axially spaced sections; and further comprising drive discs arranged intermediate and in motion-transmitting relationship with consecutive ones of said sections and having a second diameter larger than said first diameter.

7. Apparatus as defined in claim 1, said compressing means being arranged for effecting substantially radial compression of said element.

8. Apparatus as defined in claim 1; said applicator means comprising applicator rollers contacting said element immediately adjacent at least one of said surface portions for applying and distributing said mate rial on said element.

9. Apparatus as defined in claim 8, and tufts of bristles provided on the circumferential faces of said applicator rollers.

10'. Apparatus as defined in claim 8, wherein said applicator rollers are composed of axially adjacent disc portions.

11. Apparatus as defined in claim 1, said applicator means comprising at least one rotary applicator brush for receiving the foamed material and transferring it to said surface.

12. Apparatus as defined in claim 1, wherein said element has a predetermined thickness between said spaced portions, and wherein said compressing means comprises compressing members located at said spaced portions and being spaced by a distance smaller than said thickness. 

1. A cleaning apparatus comprising reservoir means for a body of foamable material in unfoamed state; converting means connected with said reservoir means for receiving from the latter unfoamed material at a first location, and for converting such material to foamed state at a second location immediately proximal said first location, said converting means comprising at least one substantially cylindrical absorbent element having an outer surface, and compressing means engaging said outer surface at spaced portions thereof for subjecting increments of said absorbent element to compression in response to movement of said apparatus over a surface to which said material is to be applied in foamed state; moving means mounting said reservoir and converting means for movement over said surface to which said material is to be applied; and applicator means for receiving the foamed material at a third location closely adjacent said second location, and for applying the foamed material to said surface.
 2. Apparatus as defined in claim 1, said absorbent element being mounted for turning movement with reference to said reservoir means; and wherein said compressing means is stationary but turnable with reference to said absorbent element.
 3. Apparatus as defined in claim 1, wherein said compressing mean comprises pressure rollers; and further comprising motion-transmitting means for effecting movement of at least one of said absorbent element and rollers with reference to the respectively other.
 4. Apparatus as defined in claim 3; and further comprising a covering of absorbent elastically compressible material provided on the exterior of at least one of said pressure rollers.
 5. Apparatus as defined in claim 1, wherein said compressing means comprises pressure members turnable about their respective longitudinal axes.
 6. Apparatus as defined in claim 1, said absorbent element having a first diameter and comprising a plurality of axially spaced sectionS; and further comprising drive discs arranged intermediate and in motion-transmitting relationship with consecutive ones of said sections and having a second diameter larger than said first diameter.
 7. Apparatus as defined in claim 1, said compressing means being arranged for effecting substantially radial compression of said element.
 8. Apparatus as defined in claim 1; said applicator means comprising applicator rollers contacting said element immediately adjacent at least one of said surface portions for applying and distributing said material on said element.
 9. Apparatus as defined in claim 8, and tufts of bristles provided on the circumferential faces of said applicator rollers.
 10. Apparatus as defined in claim 8, wherein said applicator rollers are composed of axially adjacent disc portions.
 11. Apparatus as defined in claim 1, said applicator means comprising at least one rotary applicator brush for receiving the foamed material and transferring it to said surface.
 12. Apparatus as defined in claim 1, wherein said element has a predetermined thickness between said spaced portions, and wherein said compressing means comprises compressing members located at said spaced portions and being spaced by a distance smaller than said thickness. 